[Summary of the practice guideline 'Urolithiasis' (first revision) from the Dutch College of General Practitioners]. / Samenvatting van de standaard 'Urinesteenlijden' (eerste herziening) van het Nederlands Huisartsen Genootschap.

The Dutch College of General Practitioners has revised the practice guideline 'Urolithiasis'. In the acute phase, violent colic pain is treated with diclophenac or morphine. In the post-acute phase, imaging diagnostics are performed. Initially this is ultrasound examination and, ifindicated, an x-ray of the abdomen and at a later stage, a CT scan. The recommendation to consider the use oftamsulosin in the post acute phase is new. This alpha-1 blocking agent can enhance expulsion of the stone and contribute to the relief of pain.

Study of thermal spin crossover in [Fe(II)(isoxazole)(6)](BF(4))(2) with Mössbauer spectroscopy.

(57)Fe Mössbauer spectroscopy of the mononuclear [Fe(II)(isoxazole)(6)](BF(4))(2) compound has been studied to reveal the thermal spin crossover of Fe(II) between low-spin (S = 0) and high-spin (S = 2) states. A temperature-dependent spin transition curve has been constructed with the least-square fitted data obtained from the Mössbauer spectra measured at various temperatures in the 240-60 K range during the cooling and heating cycle. The compound exhibits a temperature-dependent two-step spin transition phenomenon with T(SCO) (step 1) = 92 and T(SCO) (step 2) = 191 K. The compound has three high-spin Fe(II) sites at the highest temperature of study; among them, two have slightly different coordination environments. These two Fe(II) sites are found to undergo a spin transition, while the third Fe(II) site retains the high-spin state over the whole temperature range. Possible reasons for the formation of the two steps in the spin transition curve are discussed. The observations made from the present study are in complete agreement with those envisaged from earlier magnetic and structural studies made on [Fe(II)(isoxazole)(6)](BF(4))(2), but highlights the nature of the spin crossover mechanism.

Synthesis, crystal structure, EXAFS, and magnetic properties of catena [mu-tris(1,2-bis(tetrazol-1-yl)propane-N1,N1')iron(II)] bis(perchlorate). First crystal structure of an iron(II) spin-crossover chain compound.

[Fe(btzp)3](ClO4)2 (btzp = 1,2-bis(tetrazol-1-yl)propane) represents the first structurally characterized Fe(II) linear chain compound exhibiting thermal spin crossover. It shows a very gradual spin transition (T1/2 = 130 K) which has been followed by magnetic susceptibility measurements and 57Fe Mössbauer spectroscopy. The structure has been solved at 200 and 100 K by single-crystal X-ray analysis. It crystallizes in the trigonal space group P3c1 with Z = 2 Fe(II) units at both temperatures. The molecular structure consists of chains running along the c axis in which the Fe(II) ions are linked by three N4,N4' coordinating bis(tetrazole) ligands. The main difference between the two forms appears to be in the Fe-N bond lengths, which are 2.164(4) A at 200 K and 2.038(4) A at 100 K. The Fe-Fe separations are 7.422(1) A at 200 K and 7.273(1) A at 100 K. The EXAFS results are consistent with the crystal structure. In both spin states, the FeN6 octahedron is almost regular within the EXAFS resolution. The Fe-N distance is found as 2.16(2) A at 300 K and 2.00(2) A at 40 K. The absence of the "7 A peak" in the EXAFS spectra of [Fe(btzp)3](ClO4)2, in contrast with what has been observed for the [Fe(4-R-1,2,4-triazole)3]-(anion)2 chain compounds, confirms that this peak can be used as the signature of a metal alignment only when it involves a strongly enhanced multiple scattering M-M-M path, with M-M spacing less than 4 A. Irradiation with green light at 5 K has led to the population of the metastable high-spin state for the iron(II) ion. The nature of the spin-crossover behavior has been discussed on the basis of the structural features.